There is a known fiber-optic scanner that has a light-guiding cantilever optical fiber inside a tubular PZT (lead zirconate titanate) actuator and that supplies electrical power to pairs of electrodes provided on a surface of the PZT actuator to scan, in a desired pattern, the light emitted from a distal end of the cantilever optical fiber (refer to, for example, Patent Literature PTL 1 below). When a voltage is applied to the two pairs of electrodes, which are disposed in different quadrants on a cross-section of the PZT actuator such that the electrodes have phases shifted by 90° relative to one another, this fiber-optic scanner drives the cantilever optical fiber in two directions, thereby scanning light in a helical shape.